Julius ferdinand heinrich voigt and jacob adolf haeffner



No. 617,375. Patented Jan. [0, I899.

J. F H. VOIGT 8|. J. A. HAEF-FNER.

ELECTRICAL RESISTANCE.

(Application filed Dec. 26, 1896.)

(No Model.)

Mel

J as, I

UNITED STATES PATENT OFFICE.

JULIUS FERDINAND HEINRICH VOIGT AND JACOB ADOLF HAEFFNER, OF BOCKENHEIM, GERMANY, ASSIGNORS TO THE ROESSLER & HASSLAOHER CHEMICAL COMPANY, OF NEW YORK, N. Y.

ELECTRICAL RESISTANCE.

. SPECIFICATION forming part of Letters Patent No. 617,376, dated January 1-0, 1899.

Application an Docember 26,1895- Serial Nosvases. (Ho model.)

To all whom it may concern.-

Be it known that we, JULIUS FERDINAND HEINRICH VQIGT and J ACOB ADOLF HAEFF- NER, subjects of the King of Prussia,'Emperor 5 of Germany, and residents of the city of Bock enheim, near Frankfort-on-the-lllain, in the Kingdom of Irussia,German Empire,l1ave invented certain new and useful Improvements in Electrical Resistances, (for which we have to obtained Letters Patent in Belgium, No. 116,121, dated JunelS, 1895, and in Italy, R. G. XXX, No. 30,072, R. A.,Vol. LXXVI, No. 328, dated June 18, 1895,) of which the following is a specification.

IS This invention consists in an electrical resistance, of a thin layer of liquid metal applied by means of a firing process--after the manner in whichlustrous gold, silver, or platinum decorations are applied-4o an enamel :0 layer on a suitable base-piece. The so-formed thin metal layer contains the metal in a very finely-divided state. It can be applied in solution, being painted on after the manner of applying the well-known metalliferous lusters or liquid-bright metal colors on an enamel layer, the metal being afterward brought out by a firing process, whereby the latter is obtained as an uninterrupted layer inthe form of a band, strip, or the like. By metalliferous lusters or liquid-bright metal colors in this sense are understood a homogeneous solution of organic compounds of metals or precious metals'such as, for instance, snlfid of gold combined with balsam of sulfur or mixtures of the same in organic dissolvents, such as nitrobenzene, with-or without addition of essential oils. These so.- lutions may contain compounds of bismuth, boric acid, or phosphoric acid as combination of flux. As precions metals are toqbe understood not only gold, silver, and platinum,

.but also the elements of the platinum grouppalladium, rhodium, iridium, osmium, and

ruthenium. Aluminiumcan be used in the same manner.

The accompanying drawings illustrate a resistance of this description.

Figure 1 is a plane of resistance; a section along a: 41:.

On the base-plate a the layer of enamel is applied, and upon the latter the resistancelayer b, which is drawn forward and backward in a meandering or sinuous uninterrupted band, strip, or line of considerable lengtln For the purpose of conducting the electric fcurrent to or from the resistance either large aggregations of the resistance material are used or special metallic parts are arranged on the required places. Such an arrangement is exemplified on the drawings by the terminals 0 and d, which are soldered upon the ends of the metallic layer 12.

The metallic layer, made in the manner described, finds its application especially in rheostats for incandescent lamps which are '65 required to burn dimly at times and as a protecting device or safety-fuse for weak-current installations to protect them against strong currents, and, further, as heat-conductors for cooking and heating apparatus. In the latter cases the plate shown on the drawings is arranged in an entirely analogous manner conformable to the purpose as a jacket for cooking vessels or heating-pipes.

We. claim- 1. An electrical resistance consisting of a suitable base-piece, an enamel-layer secured thereto, and a conducting-layer of fired liquid metal, substantially as specified.

2. An electrical resistance" comprising in- 80 sulating non-combustible material, and a conducting-layer of fired liquid metal, substantially as specified.

In witness whereof we have hereunto set our hands in'presenceof two witnesses.

- JULIUS FERDINANDHEINRICH VOIGT.

JACOB ADOhF'IIAEFFNER. Witnesses: 1

LOUIS Rom, JEAN Gocxnnnscn.

Fig.2is 

